General identification codes are stored in the magnetic cards, and every card has one identification code. When a magnetic card is rushed through a card reader, the card reader could be able to identify the card user by the identification code stored in the card. But it is inconvenient for a user to take a card and rush through the card reader for identifying. So, a contactless identification code system is developed to improve the drawback of the conventional magnetic cards. The Contactless identification code system is able to identify the identification code by induction coil 12 in the card reader 11 i s able to produce a magnetic field. There is a contactless identification code IC 14 and an induction coil 15 in the card 13. An identification code is also set in this card. When the card 13 closes to the code reader, the induction coil 15 will be coupled and provides the electric power of the IC 14 according to the electromagnetic induction theory. Then the code stored in the IC will passes to the card reader 11 to identify. So, by closing the card, the card reader, but not rushing through it, can identify a user's code.
The prior art is designed for identifying one card every time. If several cards are taken close to the code reader for identifying concurrently, then the ID collision will be happened and the code identification would be wrong. Therefore, the prior art can't apply to the card identification toys or supermarket clerks for identifying several same or different items concurrently.